Objective. The Tasmanian Healthy Brain Project (THBP) is a long-term, longitudinal investigation into whether later-life tertiary education reduces ageing-related cognitive alterations and/or provides protection from dementia. Cognitive reserve (CR) has also been proposed to be protective for dementia, and brain derived neurotrophic factor (BDNF) has been implicated as having a significant role in mediating the effects of environmental enrichments in experimental studies. Method. We have investigated the THBP cohort at baseline to determine whether common allelic variation in BDNF Val66Met and APOE interact with CR to produce cognitive outcomes. This study involved 433 participants (66.7% female), aged 50-79 years (M = 62.16, SD = 6.81). A measure of CR was established through a principal components analysis (PCA) of THBP study variables (WTAR IQ, prior education and the Lifetime of Experiences Questionnaire) previously shown to contribute to the construct. Composite variables of episodic memory, working memory, executive function and language processing were also derived through PCA, with the component accounting for the largest proportion of variance retained to represent that domain. Multivariate regression analyses then assessed the main and interaction effects for predictors: age; CR; APOE; and BDNF, for each cognitive domain separately. Results. This analysis demonstrated that: (1) CR was positively associated with each cognitive domain (p < .05) while age was negatively associated with each cognitive domain (p < .05), excluding language processing, (2) individual APOE and BDNF predictors were not associated with performance in any cognitive domain, (3) BDNF moderated the association between CR and executive function performance, in that BDNF Met carriers had a significantly reduced association when compared to Val homozygotes (p < .05). Conclusions. This study has shown that CR is associated with cognitive function in healthy older adults. In addition, BDNF Met carriers demonstrated a reduced ability to generate or access CR resources when compared to BDNF Met non-carriers with respect to executive function.

Relation

2014 Neuroscience Conference, Washington DC, United States 15-19 November 2014